During my navigation of the java3d sources I noticed the IMPRESSIVE (a nightmare) copyDataToSurfacexxx() function of D3dUtil.cpp used to copy from a direct3d surface to the offscreen buffer.

I suppose that the above function is the bottleneck of Offscreen rendering with Java3D/directx.The OGL implementation uses readPixels() and therefore it's probably faster due to the ogl implementation.

Why don't reimplement it by using specific hardware-accelerated copy functions of DirectX ?

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